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PubMed2005

Distinct B-cell and T-cell lymphoproliferative disease prevalence among dog breeds indicates heritable risk.

Immunophenotypes in lymphoproliferative diseases (LPD) are prognostically significant, yet causative factors for these conditions, and specifically those associated with heritable risk, remain elusive. The full spectrum of LPD seen in humans occurs in dogs, but the incidence and lifetime risk of naturally occurring LPD differs among dog breeds. Taking advantage of the limited genetic heterogeneity that exists within dog breeds, we tested the hypothesis that the prevalence of LPD immunophenotypes would differ among different breeds. The sample population included 1,263 dogs representing 87 breeds. Immunophenotype was determined by the presence of clonal rearrangements of immunoglobulin heavy chain or T-cell receptor gamma chain. The probability of observing the number of B-cell or T-cell tumors in a particular breed or breed group was compared with three reference populations. Significance was computed using chi2 test, and logistic regression was used to confirm binomial predictions. The data show that, among 87 breeds tested, 15 showed significant differences from the prevalence of LPD immunophenotypes seen across the dog population as a whole. More significantly, elevated risk for T-cell LPD seems to have arisen ancestrally and is retained in related breed groups, whereas increased risk for B-cell disease may stem from different risk factors, or combinations of risk factors, arising during the process of breed derivation and selection. The data show that domestic dogs provide a unique and valuable resource to define factors that mediate risk as well as genes involved in the initiation of B-cell and T-cell LPD.

Animals↗
PubMedDate not supplied

Differentiation among Spanish sheep breeds using microsatellites.

Genetic variability at 18 microsatellites was analysed on the basis of individual genotypes in five Spanish breeds of sheep--Churra, Latxa, Castellana, Rasa-Aragonesa and Merino--with Awassi also being studied as a reference breed. The degree of population subdivision calculated between Spanish breeds from F(ST) diversity indices was around 7% of total variability. A high degree of reliability was obtained for individual-breed assignment from the 18 loci by using different approaches among which the Bayesian method provided to be the most efficient, with an accuracy for nine microsatellites of over 99%. Analysis of the Bayesian assignment criterion illustrated the divergence between any one breed and the others, which was highest for Awassi sheep, while no great differences were evident among the Spanish breeds. Relationships between individuals were analysed from the proportion of shared alleles. The resulting dendrogram showed a remarkable breed structure, with the highest level of clustering among members of the Spanish breeds in Latxa and the lowest in Merino sheep, the latter breed exhibiting a peculiar pattern of clustering, with animals grouped into several closely set nodes. Analysis of individual genotypes provided valuable information for understanding intra- and inter-population genetic differences and allowed for a discussion with previously reported results using populations as taxonomic units.

Alleles↗
PubMedDate not supplied

Optimum allocation of conservation funds and choice of conservation programs for a set of African cattle breeds.

Although funds for livestock conservation are limited there is little known about the optimal allocation of conservation funds. A new algorithm was used to allocate Mio US dollar 1, 2, 3, 5 or unlimited funds, discounted over 50 years, on 23 African cattle breeds conserved with four different possible conservation programs. Additionally, Mio US dollar 1 was preferably allocated to breeds with special traits. The conceptional in situ conservation programs strongly involve breeders and give them part of the responsibility for the conservation of the breed. Therefore, the pure in situ conservation was more efficient than cryoconservation or combined in situ and cryoconservation. The average annual discounted conservation cost for a breed can be as low as US dollar 1000 to US dollar 4400 depending on the design of the conservation program and the economic situation of the country of conservation. The choice of the breeds and the optimal conservation program and the amount of money allocated to each breed depend on many factors such as the amount of funds available, the conservation potential of each breed, the effects of the conservation program as well as its cost. With Mio US dollar 1, 64% of the present diversity could be maintained over 50 years, which is 13% more than would be maintained if no conservation measures were implemented. Special traits could be conserved with a rather small amount of the total funds. Diversity can not be conserved completely, not even with unlimited funds. A maximum of 92% of the present diversity could be conserved with Mio US dollar 10, leaving 8% of the diversity to unpredictable happenings. The suggested algorithm proved to be useful for optimal allocation of conservation funds. It allocated the funds optimally among breeds by identifying the most suited conservation program for each breed, also accounting for differences in currency exchange rates between the different countries.

Africa↗
PubMed2002

The use of passive injectable transponders in fattening lambs from birth to slaughter: effects of injection position, age, and breed.

A total of 1,159 Tiris half-duplex passive injectable transponders (PIT) of 32-mm length were used to study the electronic identification of 618 fattening lambs of two breeds used for different production purposes (Ripollesa, meat breed, n = 271, and Manchega, dairy breed, n = 347). The lambs were s.c. injected in the armpit and the retro-auricular positions at 2, 15, and 30 d of age. All lambs were also tagged with a small plastic ear tag after birth. A group of 76 lambs were injected only in the right armpit and were kept for breeding. The PIT losses, breakages, and electronic failures were evaluated at weekly weight recordings throughout the fattening period using two types of hand-held transceivers. Fattened lambs were harvested in a commercial abattoir between 3 and 4 mo of age when they reached market weight (11 to 12 kg hot carcass weight). The total number of PIT that fell or broke in the slaughtering line, the location method, and the recovery time were recorded. On the farm PIT losses were not affected (P > 0.05) by age at injection, injection position, or breed. Mean losses of PIT and ear tags during the same period were 5% and 6.3%, respectively (P > 0.05). No PIT breakages or failures were observed during the fattening period. Mean recovery of PIT in the abattoir (85.6%) was affected (P < 0.05) by breed and injection position. Losses of PIT in the abattoir were greater (P < 0.05) in the Ripollesa breed (18.4%) than in Manchega (10.0%), and for both breeds losses were greater (P < 0.05) in the retro-auricular than in the armpit positions (18.6 vs 10.8%, respectively). The percentage of PIT broken during slaughtering was low (0.3%). The mean recovery times (18 +/- 2 s) were not affected (P > 0.05) by breed, injection position, or age, thus allowing a harvesting speed of 200 lambs/h on average. In conclusion, the injection of 32-mm PIT into the armpit or the retro-auricular region is not recommended as a practice for the electronic identification of fattening lambs, even though they perform similarly to small plastic ear tags. This is partly a consequence of the PIT losses observed on the farm but mainly because of the difficulties with recovering the PIT in the abattoir. More research will determine whether the use of smaller transponders or injection in other positions could improve their performance in fattening lambs.

Abattoirs↗
PubMed1981

Comparison of three-breed and backcross swine for litter productivity and postweaning performance.

Duroc, Hampshire and Yorkshire boars were mated with crossbred gilts of Duroc-Hampshire, Duroc-Yorkshire and Hampshire-Yorkshire breeding to produce 133 three-breed and 259 backcross litters that were farrowed during four seasons beginning in the fall of 1975. Three-breed cross litters were .31 +/- .27, .57 +/- .24 and .50 +/- .24 pigs larger than backcross litters at birth, 21 and 42 days, respectively, and .6 +/- .34, 2.3 +/- 1.2 and 5.4 +/- 2.4 kg heavier at these ages. The differences in average pig weight and survival percentage were small. Three-breed cross litters gained faster (.024 +/- .007 kg/day) and were younger (-4.7 +/- 1.5 days) at 100 kilograms. Three-breed cross pigs were about 3% more efficient than backcross pigs. The differences in average backfat probe and average daily feed intake were small and not significant. Breed of sire contrasts for litter traits were small and not significant. However, significant differences between sire breeds existed for postweaning performance. Also, few differences between crossbred dam groups were significant for litter size or litter weight, but significant differences in postweaning performance existed between progeny of crossbred dam groups. In general, pigs with Duroc breeding had the fastest growth rate and those with Hampshire breeding were the leanest.

Animals↗
PubMed1984

Breed and sire effects on crossbred lamb production from Panama ewes and on spermatozoan midpiece length.

Three-hundred mature Panama-type range ewes were mated to Clun Forest, Dorset, Border Leicester, Polypay and Suffolk rams during the 1979 and 1980 breeding seasons. Sire breed and ram within breed effects on lamb growth, ewe reproduction, spermatozoan midpiece length (MPL) and midpiece length coefficient of variation (MPLCV) were examined. Associations among MPL and MPLCV and economically important traits also were assessed. Suffolk-sired lambs weighted .18, 2.0 and 1.5 kg more, at birth, weaning and post-weaning, respectively, than the average of all groups. Dorset-sired lambs had the lightest postweaning weight. Variation was greatest among Suffolk rams for average weaning and postweaning weights of their progeny. The Border Leicester breed had the least among ram variation for progeny weaning weight; while variation among Dorset rams was least for progeny postweaning weight. Fertility (ewes lambing/ewe exposed) and prolificacy (lambs born/ewe lambing) of the rams' mates were not influenced significantly by sire breed. Lamb mortality also was not influenced by breed of sire nor by rams within a breed. For variation in MPL, 26.4% was due to the breed effect (P less than or equal to .01) and 21.6% was attributable to ram variation within a breed (P less than or equal to .01). Clun Forest rams had the longest average MPL and greatest MPLCV, while Dorsets had the shortest MPL and smallest MPLCV. There were no important associations between either MPL or MPLCV and any of the economic traits.

Animals↗
PubMed1993

Effects of formaldehyde fumigation of housing on carotenoid pigmentation in three breeds of chickens.

Three breeds of chickens (two broiler breeds, A and B, and one layer breed, C) were raised from 1 day to 3 wk of age in either standard housing or housing additionally fumigated with formaldehyde. Groups of chicks from each breed in both housings received either regular poultry starter ration or this ration supplemented with marigold meal. At 3 wk of age, chicks of all three breeds had higher (111, 113, and 115%) mean body weights when raised in fumigated housing. There was no significant effect of supplemental carotenoids on body weight. Chicks of all three breeds raised in fumigated housing had significantly higher plasma carotenoid concentrations when fed either regular or supplemented feed, and, with the exception of Breed A on regular feed, also had significantly increased skin carotenoid values. No significant differences among breeds in plasma or skin carotenoid values were seen in chicks fed regular ration. However, significant differences were seen among groups of chicks fed supplemental carotenoids. The layer breed, C, had the highest percentage increase in carotenoid pigmentation when fed the carotenoid-supplemented diet in fumigated housing.

Animal Feed↗
PubMed2002

[Genetic polymorphism of Russian, European, and Asian chicken breeds as revealed with DNA and protein markers].

The variation in polymorphic DNA (RAPD and minisatellite) and protein markers was compared for nine Russian chicken breeds differing in morphological and productivity types and in origin, three European egg breeds, and three broiler breeds of the Asian origin. Genetic diversity indices were calculated for each breed group and each marker type and were used to construct dendrograms of genetic similarity. In all breed groups, minisatellites and RAPD markers revealed higher genetic diversity as compared with protein markers. With any type of markers, genetic diversity of the Russian and Asian broiler breeds proved to be significantly higher than that of the European egg breeds. The differentiating potentialities of molecular and genetic biochemical markers at the breed level and the origin of the Russian chicken breeds are discussed.

Albumins↗
PubMed2003

Genetic diversity of microsatellite loci in fifty-six Chinese native pig breeds.

The genetic diversity of fifty-six indigenous pig breeds in China, and three introduced pig breeds (Duroc, Landrace and Large White) was surveyed using twenty-seven microsatellites recommended by the International Society for Animal Genetics (IS-AG) and Food and Agriculture Organization (FAO). By means of the allele frequencies, mean heterozygosity, effective number of alleles, estimator of gene differentiation, polymorphism information content, genetic distance and dendrogram analysis, the genetic variability and population structure of native pig breeds were estimated. Genetic variabilities within native pig breeds are as follows: Effective number of alleles vary from 2.12 to 9.03, from 0.44 to 0.87 for mean heterozygosity, from 0.39 to 0.86 for polymorphism information content. Nei's genetic distance and Nei's standard genetic distance were estimated and used to construct UPGMA and NJ dendrograms, which were evaluated by the bootstrap test. Fifty-six Chinese indigenous pig breeds were clustered into twelve groups based on the dendrogram. Compared with the classification in Pig Breeds in China, I, II and III groups in the study are equivalent to North-China type, IV group basically accords with Lower-Changjiang River Basin type, V, VI, VII, VIII and IX groups quite correspond with Central-China type, X and XI group largely correspond to South-China type, the last group, XII is equal to South-west type at large. Suggestions that the conservation farms together with conservation areas are appropriate methods for the preservation of native pig breeds in our country were proposed. The results could provide basic molecular data for the research on the germplasm characteristics of local breeds in our country and scientific basis for the conservation and utilization of those breeds.

Alleles↗
PubMed2006

PrP gene polymorphism in sheep breeds in Slovakia and susceptibility to scrapie.

We analyzed the prion protein (PrP) genotype based on the codons 136, 154 and 171 and assigned to five risk groups (R1-R5) in healthy and scrapie-affected sheep in Slovakia. In healthy (asymptomatic) population, 119 Merino, 106 Improved Valachian, 117 Tsigai, and 48 Suffolk breeds were tested. Among the asymptomatic sheep, the low-risk genotypes R1 and R2 were most abundant in Suffolk (94%) and Merino (84%) breeds, followed by Tsigai (58%) and Improved Valachian (40%) breeds. The medium-risk group R3 was most frequent in Improved Valachian (31%) breed, followed by Tsigai (21%), Merino (10%), and Suffolk (6%) breeds. The occurrence of high-risk groups R4 and R5 was none in Suffolk breed, followed by Merino (6%), Tsigai (21%), and Improved Valachian (30%) breeds. Since 2003, altogether 48 cases of scrapie have been confirmed in Tsigai (38), Merino (4), Improved Valachian (2), Improved Valachian x Tsigai (3), and Suffolk (1) breeds. Among sheep with scrapie, Merino breed belonged to the medium-risk group R3. The majority of scrapie-affected Tsigai sheep were classified into high-risk R5 (50%) and medium-risk R3 (42%) groups. We showed an association of scrapie with medium- and high-risk groups of PrP genotype in Slovakia. In particular, the glutamine at position 171 appears to be of major importance for the susceptibility to scrapie.

Animals↗
PubMed2001

A whole genome scan for differences in recombination rates among three Bos taurus breeds.

Twenty paternal half-sib families of a granddaughter design were genotyped for 265 genetic markers, most of them microsatellites. These were 16 Holstein families, 3 Simmental families, and 1 Brown Swiss family. The number of sires per breed was 872, 170, and 32, respectively. Two-point recombination rates were estimated both jointly for all breeds and each single breed separately. Of 1168 marker intervals, 865 provided estimates for at least two breeds. Differences between breeds were tested by likelihood ratio tests. Four marker intervals, representing three genomic regions on BTA19, BTA24, and BTA27, show a significant impact of the breed at a false discovery rate of 0.23 and indicate a genetic component of observed heterogeneity of recombination. The variability of recombination rates between cattle breeds might not be a common feature of the whole genome, but rather might be restricted to certain chromosomal segments. Thus, attention should be paid to heterogeneities when pooling data of such regions from different breeds.

Animals↗
PubMed2006

Hematological parameters in brood-rearing great tits in relation to habitat, multiple breeding and sex.

Very little is known about the causes and correlates for variation of individual condition in the wild. However, such knowledge is essential for understanding the mechanisms that mediate environmental effects to populations. We studied the variation of several hematological condition indices (hematocrit, albumin, globulin and triglyceride concentrations, albumin/globulin ratio, lymphocyte and heterophile concentrations and heterophile/lymphocyte ratio) and body mass in brood-rearing great tits (Parus major) in relation to habitat, multiple breeding and gender. Although great tits prefer deciduous forest to coniferous forests, individuals breeding in coniferous forests tended to be in a superior health state than those breeding in deciduous habitat. We suggest that this difference in adult condition can be caused by differences in breeding densities between habitats. Although there was some variation in condition indices between breeding attempts, none of these parameters measured at the end of the first breeding attempt predicted the probability of double breeding. We also found that females were in poorer condition and probably more stressed than males, both during the first and the second breeding attempt. These findings demonstrate that hematological parameters can be used to assess spatial and temporal variation of individual condition in the wild.

Animals↗
PubMed2006

A questionnaire-based study of gestation, parturition and neonatal mortality in pedigree breeding cats in the UK.

This study was based on a convenience-sampling questionnaire study of pedigree cat breeding in the UK. Data were collated for the births of 1,056 litters from 14 different pedigree breeds and 942 different households. Significant relationships between various outcomes and relevant predictors were assessed by multiple linear regression or logistic regression as appropriate. The overall mean gestation length of 65.1 days varied significantly between the breeds (P<0.0001), and larger litter sizes were associated with shorter gestation lengths (P=0.04). The mean litter size of 4.6 kittens also varied significantly according to breed (P<0.0001). The weight of kittens born alive (overall mean 93.5 g) increased with longer gestation lengths (P=0.0003), decreased with larger litter sizes (P<0.0001) and varied between the breeds (P<0.0001). A total of 8.0% of pregnancies resulted in a caesarean section, with a higher risk associated with smaller litter sizes (P=0.002). Although the frequency of caesarean sections varied from 0 to 18.5% between individual breeds, breed itself was not shown to have a significant independent effect on this likelihood. A mean of 7.2% of all the kittens were stillborn, which varied according to breed (P=0.0003), and the risk of a stillborn kitten increased with litter size (P=0.0001), and with the presence of congenital defects in the litter (P=0.0002). The mean kitten mortality between birth and 8 weeks of age was 9.1%, and the majority of these occurred in the first week of life. Parturition intervals varied widely. The duration of first stage of labour was less than 2h in 82.9% of cats. The interval between the birth of the first and last kitten was less than 6h in 85.7%, but more than 48 h in three cats. A maximum of 48 h was recorded between the births of individual kittens in unassisted deliveries.

Animals↗
PubMed1997

Fertility of the male alpaca: effect of daily consecutive breeding.

The fertility of the male alpaca under different frequencies of daily consecutive matings was evaluated. Fifteen adult male Huacaya alpacas were divided randomly into three groups of five each to breed lactating female alpacas. The schedule of daily matings was two, four and six consecutive breeding per group and for nine consecutive days. Ovulation was determined by progesterone at seven days after breeding. Pregnancy was determined by ultrasonography at 15 and 30 days after breeding. Two hundred and eighty females were bred with some males not fulfilling their schedule of breeding. There were differences (P < 0.05) in the fertility rate of males breeding two and four times daily (76%) in contrast to 59% for males breeding six times. There were also differences (P < 0.05) in the fertility of individual males. Length of copulation was affected (P < 0.05) by schedule of matings, day of breeding and male. Ovulation was independent of length of copulation. Overall, it seems the fertility of the male alpaca is affected significantly when consecutive matings are over four times a day and for nine consecutive days.

Animals↗
PubMed2004

DGAT1 polymorphism in Bos indicus and Bos taurus cattle breeds.

As a result of multiple QTL-mapping projects in recent years, a quantitative trait locus for milk fat percentage and milk yield has been described on BTA14. Recent reports name the acyl-CoA : diacylglycerol acyltransferase (DGAT1) gene on BTA14 as a potential candidate gene, with a nonconservative substitution of lysine by alanine (K232A) producing a major effect on milk composition and yield. DGAT1K appears to be the ancestral allele and the K232A substitution probably occurred after the divergence of the Bos indicus and Bos taurus lineages. These findings prompted us to genotype 1748 DNA samples of 38 different Bos taurus and Bos indicus cattle breeds from 13 countries on five continents (Europe, Africa, Asia, North America and South America), to examine the occurrence of the DGAT1 polymorphism and characterize the K232A substitution in cattle breeds of different origins and selected for different purposes (e.g., beef, dairy and dual purpose). Calculating pairwise FST values for pooled subpopulations showed least divergence for Bos indicus breeds with high milk fat percentage. Fixation of DGAT1A was found in some Bos taurus breeds and fixation of DGAT1K in one Bos indicus breed. Breeds of no known organized breeding background from the Near East domestication centre of Bos taurus and taurine African N'Dama cattle were found to possess intermediate frequencies of DGAT1K. While beef breeds tended to harbour higher DGAT1A levels, dairy cattle showed everything from very low levels of DGAT1K to unexpectedly high frequencies of this allele.

Acyltransferases↗
PubMed2004

Strong phylogeographic relationships among three goat breeds from the Canary Islands.

We partially sequenced the mitochondrial D-loop region in 47 individuals from eleven Spanish and foreign goat breeds. Phylogenetic analysis of these sequences allowed us to identify a particular D-loop haplotype shared by individuals from the Palmera, Majorera and Tinerfeña Canarian breeds. Genotyping of 281 goats from 17 different breeds by PCR-Hpall RFLP evidenced that the geographical distribution of this haplotype is restricted to the Canary Islands. This ancestral mitochondrial haplotype might originate in the domestic goat herds brought by the native Canarian inhabitants approximately 3000 years ago. Although we observed other miscellaneous D-loop haplotypes in the Palmera, Majorera and Tinerfeña breeds, any of them allowed us to group individuals from these three populations in a single cluster, a feature that suggests that these haplotypes might have diverse origins. The remarkable degree of phylogeographic structure of the Canary goat breeds with regard to other Spanish and foreign populations might be attributed to the isolation of these breeds in the Canary Islands for approximately 2500 years, without exposure to the migratory movements and commercial trading events that probably affected the genesis of most domestic goat breeds worldwide. The Canarian D-loop haplotype can be efficiently genotyped by using DNA isolated from milk and cheese samples, which paves the way for the future establishment of a Canary breed identity test for these dairy products.

Animals↗
PubMed2004

Analysis of the genetic structure of endangered bovine breeds from the Western Pyrenees using DNA microsatellite markers.

In the Western Pyrenees, three out of four native cattle breeds are in grave danger of extinction. Genetic variation of all four breeds was assessed by analyzing 478 animals using 11 microsatellite markers. A moderate/high within-breed variability was found, a favorable factor to consider when planning conservation and improvement programs. Interestingly, the only selected commercial breed, the Pirenaica, showed depressed heterozygosity levels and a low average number of alleles, perhaps explainable by intensive human selection exacerbated by a bottleneck effect. The Pirenaica also exhibited pronounced genetic differences and was the largest contributor of diversity among the breeds from the Western Pyrenees. Among endangered cattle breeds from this region, our results highlight the singularity of the Betizu. Geographic isolation among herds may be responsible for the large F(IS) value found in the Betizu breed. Lastly, our study suggests that the use of highly selected breeds may be one of the causes of distortion in phylogenetic analyses.

Alleles↗
PubMed2000

Are DNA profiles breed-specific? A pilot study in pigs.

In this study, DNA fingerprints from 32 unrelated domestic pigs were analysed and screened for breed-specificity. Three breed groups were analysed: Chinese Meishan, Large White and a collection of other European breeds. Ninety-three distinct and variable bands were used to estimate genetic distances between the animals. Between the groups these individual genetic distances substantially exceeded those within a group. Linear discriminant analysis showed that the 23 most common DNA fragments revealed sufficient breed-specificity as to assign each pig correctly to its breed or breed group. These findings, although based on a small sample, indicate that selective use of minisatellite variation in pigs appears to be a valuable novel approach toward the development of breed DNA profiles and the resolution of breed relationships.

Animals↗